Fiter design is the process of designing a filter.

learn more… | top users | synonyms

0
votes
1answer
49 views

Any good C# library for signal processing?

Does anyone can link me to a good C# DSP library? I saw some good C++ libraries but I don't have much with C++. Is there any way to wrap them ? My main porpuse is to apply some filters(Lowpass, ...
0
votes
0answers
45 views

What is Single pole filter?

Can anybody tell me why do we use single pole filter? And may be an example of Single pole filter in matlab. Good literature recommendations are also welcomed.Moreover, that would be good if anyone ...
2
votes
1answer
71 views

How to test digital filters?

First the question(s): How should I write unit tests for a digital filter (band-pass/band-stop) in software? What should I be testing? Is there any sort of canonical test suite for filtering? ...
0
votes
0answers
24 views

How to determine cut off frequency for high pass filter using spectral density?

I have filtered out the low frequency noise from the signal. For further analysis, I want to compare it with FIR filters (for which I require cut off frequency). Hence, I took the power density ...
0
votes
1answer
31 views

Fir filter not working according to frequency response

I have designed a FIR filter with following parameters fs=30, f_pass1 = 1, stop1 = 0.5, f_pass2 = 3, f_stop2 = 4, A_pass = 1,A_stop = 40 Here is code : ...
0
votes
0answers
10 views

Difference between Sparse filters and Multiplier filters

I googled this differences but i haven't get any exact resources about this.Some papers said Sparse FIR filters, others Multipliers FIR filters.But no one said whether this is same or not. So my ...
0
votes
1answer
26 views

How to normalize predesigned IIR filter coefficients to have unity gain?

There is a low pass filter with difference equation already provided. $$ y_n = (x_n - 2x_{n-6} + x_{n-12}) - (-2y_{n-1} + y_{n-2}) $$ $$ a_0 = 1, a_1 = -2, a_2 = 1 $$ $$ b_0 = 1, b_6 = -2, b_{12} = ...
0
votes
0answers
15 views

Identify correlated colored noises that affect a signal

In the process of signal + noise, which is not stationary. In this case how could I a. determine what autocorrelated noise colors affect a signal. b. What mix of correlated colors affect the signal ...
2
votes
2answers
64 views

How to design an inverse for a Butterworth low-pass filter?

I have a signal that has a spectral shape very similar to the transfer function of a second-order lowpass filter (butterworth design). I would like to whiten the spectrum of this spectrum in the ...
0
votes
1answer
33 views

Filter implementation and alternatives

I'm learning of digital filters and found a question asking why a filter with a impulse response $$h[n]= \begin{cases} \frac{1}{n^2+3n+2} & n\geq 0 \\ 0 & n<0 \\ ...
0
votes
1answer
50 views

Possible to implement simple IIR filter with greater than 6 db/octave slope?

I am using the following IIR code as a low-pass filter in a software project, and it works great. However, I would like the slope of the filter to be much steeper as the one here seems to be very ...
0
votes
1answer
27 views

What is the Reference tap of an equalizer (FIR Filter)

Currently I'm using the built-in Equalizer (EQ) object from Matlab to equalize my signal. For the EQ there is a parameter called the Reference tap. With different value of the reference tap i got also ...
1
vote
1answer
33 views

Necessity of Cyclic Prefix in OFDM

I have a question on CP-OFDM. In recent years people are talking about filter bank approach where they are trying to filter out the out of band side lobes using filters. Besides they are presuming ...
0
votes
0answers
33 views

Any simple Digital All-Pass Filter Design Tools?

I would like to be able to implement an All-Pass filter with a frequency-dependent group delay. I need a maximum group delay at low frequency of about 20 samples (for Fs = 44.1kHz), and it needs to ...
0
votes
2answers
103 views

Which filter for an audio equalizer

I’m new to DSP and I have to do an audio equalizer in c++. I did a lot of research about it and tried some stuff in the last month, but I’m a little overwhelmed with all those informations and it’s ...
0
votes
0answers
30 views

Deriche recursive filter using OpenCV

Is it possible to create a Deriche recursive filter using opencv (the Deriche filter is a blur that minimizes noise and preserves edges for later edge detection)? I can create one using CPU code, but ...
0
votes
0answers
49 views

ECG noise filtering using FIR Bandpass Filter

I am new to signal processing and examine ECG data corrupted with noise. The clean data has a frequency spectrum like this. And the corrupted one looks like this (sorry for the different scale) ...
0
votes
1answer
32 views

Help with Hankel Tranform filters

I found a filter for Hankel Transform . As far as i understand this is effectively used as an approximation for J0(x) and J1(x) . But how will the change in input affect these filter terms (eg J0(r) ...
1
vote
1answer
32 views

Equiripple Filter-Design

I have a requirement to design minimax filter with linear programing (linprog in MATLAB). To build the filter I must choose vector $\omega$ (frequency sample), how ...
1
vote
1answer
77 views

Sampling frequency and oversampling factor

A quite naïve question. I need some clarification regarding choosing the sampling frequency and oversampling factor. The scenario is as follows: I have an OQPSK modulated sequence with symbol rate 2 ...
0
votes
0answers
24 views

Can't make a Wiener filter work

I have two wav signals, one desired and the other one an unwanted signal perturbing the first one. I'm trying to implement a Wiener filter to reduce the second one, but when using the sound function I ...
1
vote
2answers
57 views

Find Stopband Edge Frequency

I tried to find the stopband edge frequency.I know that the signal amplitude falls to -3 dB below the passband edge frequency.I examine a lot of DSP books so i don't any information about how to ...
0
votes
0answers
48 views

Half Sine Pulse Shaping design

The standard of 802.15.4 specfies the following 'The chip sequences representing each data symbol are modulated onto the carrier using O-QPSK with halfsine pulse shaping.' For pulse shaping the ...
3
votes
1answer
49 views

What windowed Sinc might be closest to a Parks–McClellan low-pass filter?

In another question on dsp.stackexchange, a statement was made that the output of MATLAB firpm() or firls() for an anti-alias low-pass filter was "close" to the coefficients of a windowed-Sinc ...
0
votes
0answers
40 views

time domain non stationary time series individual colored noise identification algorithm

One of the methods for identification of modulated colored (stationary) noises is that of lag 1 autocorrelation power law noise identification algorithm. This method can determine the dominant noise ...
1
vote
1answer
17 views

Calculating the network function of a filter

Given a system, that behaves as a 1st order filter with network function $H(s)$. We input: $$v_1 (t)=1+3\cos(10^4 t)$$ And we obtain as output: $$v_2(t)=1+1.5\cos \left(10^4 t ...
0
votes
1answer
40 views

Convert low pass continuous time filter design to bandpass, discrete time

I am trying to convert the continuous time transfer function of a second order lowpass Butterworth filter is given by: To a bandpass fourth order bandpass digital filter, I first apply the mapping ...
0
votes
0answers
21 views

Filtering with Gaussian Shape

I would like to know how to properly filter a cosinus wave signal with a Gaussian Filter. I thought to use 'conv' to perform it. My code as follows : ...
0
votes
1answer
47 views

Parks-McClellan - compiling C++ code from Iowa Hills page [closed]

I am trying to compile C++ code for FIR filter design using Parks-McClellan algorithm from http://www.iowahills.com/Example%20Code/NewParksMcClellan.txt . However, I cannot find the following header ...
3
votes
2answers
119 views

How do can we cancel out noises while listening voice on headphones?

It's a common problem that while talking with the another person on Smart phones with the help of regular headphones,we get very annoying sounds at background . The opposite person's voice gets mixed ...
0
votes
1answer
48 views

Help choosing coefficients for a simple FIR filter to extract DC component

I am a beginner in design of digital filters... I have just completed Coursera's Linear Circuits course! I have a signal which is sampled at 50 Hz where the DC component has a value of 800000 and ...
0
votes
1answer
44 views

What is sound output delay of a band pass filter at different freqencies?

I measured that a 2-pole band pass filter, given imput audio of different frequencies, outputs an audio signal with different time delay. At 440Hz, the time delay between of the input audio and the ...
0
votes
1answer
15 views

Concepts Surrounding First Two Samples in Difference Equation

I'm attempting to construct a difference equation in matlab for the function u(n) and find the auto-correlation matrix R. I'm following the technique as is defined by my text below: The system I'm ...
0
votes
2answers
65 views

Design Filter with Arbitrary Magnitude and Phase Response in Matlab

Does anyone know of a way to design a filter with arbitrary magnitude and phase response in Matlab?
1
vote
0answers
30 views

Phase Linearization

Does anyone know of some simple algorithms to linearize the phase response of a filter. I have a notch filter with a non-linear phase response. I basically need an all pass filter (so that the ...
0
votes
0answers
21 views

high amplitude filter for same frequency signals

I'm analysing quasi-periodic movement (push ups). Each push up can take 1-5 seconds with stops or jerky movement along the way. I already used Savitzky-Golay filter. I want to filter out low ...
2
votes
0answers
40 views

How many different filters are needed for in an iterated filter bank?

I'm trying to implement an iterated filter bank as described in the Subband coding chapter of the Really Friendly Guide to Wavelets. However, the text seems to suggest that The advantage of this ...
0
votes
1answer
48 views

Matlab: is a highpass filter what I want, to obtain my required spectrogram? How do I design/apply this? (pic included)

The axes are wrong in the spectrogram. I have an audio wav file, and I know the sampling rate. this is read into the audioData variable. The audio is 1 channel. selected window length I believe (can't ...
0
votes
1answer
83 views

FIR design using firpm (Parks-Mclellan)

Can you please help me with some ideas on how to implement an FIR filter in Matlab using Parks-Mclellan algorithm? My specifications are the passband cut-off frequency, the transition bandwidth. The ...
0
votes
0answers
29 views

Filter signal1 from evolving frequency response of signal2

I'm a composer (of music) starting out with signal processing. I'm also reasonably proficient in C at this point. I'm not even sure if what I'm trying to do is possible, because I can't yet find an ...
0
votes
1answer
207 views

FIR filter coefficients from frequency responses

I have frequency responses of FIR filter of order 13 from obtained 50 frequency samples. How can I get FIR filter coefficients of order 13? For example, in MATLAB a lot of possible ways I tried ; I ...
0
votes
0answers
21 views

Filtering an image with a helmholtz-type equation

I'm attempting to apply the following PDE as an image filter to smooth a discrete heightmap with a helmholtz-type equation as described in this paper. It seemed like an interesting alternative to a ...
0
votes
1answer
39 views

Why this two FIR filters have the same amplitude but different phase response

Why a filter of the form $$ 1+a_0 z^{-1} +a_1 z^{-2}+ a_2 z^{-3} $$ has the same amplitude response when in the reversed form $$ a_2+a_1 z^{-1} +a_0 z^{-2}+z^{-3} $$ but the phase response is ...
-1
votes
1answer
72 views

Spectral leakage issue cannot solved using windowing

I am designing a frequency lowpass filter using FFT&IFFT. My test data is a time series with a large DC component (the pink curve). Before the FFT, the time series was detrended (curve fitting) to ...
0
votes
1answer
39 views

transfer function of wiener filter

I am trying to understand the function of a Wiener filter. I get that the Wiener filter minimizes the mean square error between the estimated random process and the desired process. Does this mean ...
0
votes
1answer
58 views

How to account for sample rate in a FIR Digital Filter?

As a learning exercise I am trying to simulate a simple notch filter with Matlab. For test purposes I use Matlab to simulate sinewaves of various frequencies and plot frequency vs. gain so I can see ...
1
vote
0answers
25 views

scaling issue when using scypy's firwin2 to get coefficients for a filter

I am trying to use SciPy's firwin2 command to get the coefficients that correspond to a filter of my creating. I took white noise in Audacity, applied an ...
0
votes
1answer
47 views

Tradeoff between Filter Order and Sections

I have designed a bandpass IIR butterworth filter with desired response using the MATLAB FDAtool with the configuration shown in the figure below Since this is multistage implementation, when I ...
0
votes
1answer
54 views

1D filter for speed input and noisy position sensor

I was tasked with designing a filter to smooth out a translating table. The system, we command a speed and a desired position, and measure it with two noisy position sensors. The commanded speed is ...
1
vote
0answers
65 views

Basic “filtering” in digital communications

I am completely stuck on solving some problems for my digital communications class. Junior level undergrad class, so fairly basic. I have been searching around all day for related articles etc but ...